Recovery of fugitive dust

Abstract

A method for the recovery of fugitive dust by encapsulation of fugitive calcined coke dust into agglomerate balls having substantial compressive strength which involves the steps of water-wetting calcined coke dust with an aqueous solution of a polyethoxylated alkyl phenol wetting agent to provide moist coke dust and thereafter admixing the moist dust with an asphalt emulsion whereby nonfriable agglomerate balls of asphalt encapsulated calcined coke dust can be recovered.

What is claimed is: 
     
       1. A method of encapsulation of fugitive carbonaceous dust comprising first adding at least a water-wetting amount of a wetting agent for the dust and sufficient water to moisten a quantity of carbonaceous dust to said quantity of carbonaceous dust and thereafter admixing an encapsulating amount of an asphalt emulsion with said moistened quantity of carbonaceous dust and recovering balls of agglomerate encapsulated dust, said asphalt comprising from 2 to 5 wt% of said dust. 
     
     
       2. A method according to claim 1 wherein said wetting agent is added as a dilute aqueous solution and the admixing is carried out as soon as said dust is water-wetted. 
     
     
       3. A method according to claim 1 wherein from 1 to 3 weight percent of the wetting agent is added as an aqueous solution with an amount of water sufficient to provide about the optimum moisture content of said water in said dust. 
     
     
       4. A method according to claim 1 wherein said binder is obtained from an emulsion and is asphalt in an amount of from 2 to 5 weight percent based on the weight of the dust. 
     
     
       5. A method according to claim 3 wherein the wetting agent is a polyethoxylated nonylphenol containing 10 moles of ethylene oxide for each mole of nonylphenol, said emulsion provides from 2 to 5 weight percent of asphalt and said amount of water ranges from 0.5 to 2.5 weight parts per weight part of dust. 
     
     
       6. A method as defined in claim 1 wherein the water wetting agent has an HLB between 10 and 16. 
     
     
       7. A method as defined in claim 1 wherein the asphalt emulsion comprises water external emulsion. 
     
     
       8. A method as defined in claim 7 wherein the emulsion comprises from 60 to 65 weight percent asphalt. 
     
     
       9. A method as defined in claim 1 wherein the balls are from 1 to 4 cm in diameter. 
     
     
       10. A method as defined in claim 9 wherein the balls have a compressive strength of at least 5 psi. 
     
     
       11. A method as defined in claim 1 wherein the admixing step is carried out at a temperature of between 20° C. and 50° C. 
     
     
       12. A method as defined in claim 1 wherein the carbonaceous dust is calcined coke dust.